There are legal methods- that the school can use which would give them the name of the account holder... If you don't know what they are- then be prepared that when the school finds out- expect your phone to be confiscated and/or "suspension or whatever" as well.
The prank may have been good- but every prankster understands there are consequences IF they get caught... you, and anyone else who called the 'hidden' phone, should just be ready for the consequences.
If you read the punishment your school has regarding CELL PHONE USE-
our first offense is pick up at the end of the day, second is pick up after a week I think, third is they keep it to the end of the year....sounds like he wants to jump straight to 3rd offense...
That's the punishment for getting caught using a phone for the third time.
You realise that the school can do whatever they want, right? And, in this situation, they deemed that the use of the cell phone and the disruption they feel it caused deems going directly to the 3rd punishment.. and guess what? They can do that.
Great prank- not fully thought out- you are lined up to get caught- and, the best part is, if this makes the school just out-right ban cell phones at school... you and your friends will be the great group who made it happen.